A technique for film grain noise extraction, modeling and synthesis is studied and applied to high-definition video coding in this paper. Film grain noise enhances the natural appearance of pictures in high-definition...
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A technique for film grain noise extraction, modeling and synthesis is studied and applied to high-definition video coding in this paper. Film grain noise enhances the natural appearance of pictures in high-definition video and should be preserved in coded video. However, the coding of video contents with film grain noise is expensive. In previous art, it was proposed to enhance the coding performance by extracting film grain noise from the input video at the encoder as a preprocessing step, and by resynthesizing and adding it back to the decoded video at the decoder as a postprocessing step. In a novel implementation of this approach, we first remove film grain noise from image/video with a variational denoising approach without distorting its original content. Then, we present a parametric model (consisting of a small set of parameters) to generate film grain noise that is close to the actual one in terms of a couple of observed statistical properties, such as the power spectral density and the crosschannel spectral correlation. Under this framework, the coding gain of denoised video is higher while the visual quality of the final reconstructed video is well preserved. Experimental results are provided to demonstrate the superior performance of the proposed approach.
This work deals with Boolean functions of non-linear and linear basis. The Boolean random functions of non-linear basis were proposed by Serra (1988, 1989). These functions are generated through a Poisson point proces...
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This work deals with Boolean functions of non-linear and linear basis. The Boolean random functions of non-linear basis were proposed by Serra (1988, 1989). These functions are generated through a Poisson point process upon which a family of independent functions, called gel functions, are installed. This process of installation consists in taking the Sup (supremum), point to point, of the result of placing the germ functions upon the points of the Poisson process. Boolean functions of linear basis, which are defined and proposed in this paper, are generated in the same manner as the non-linear functions but with a modified installation process. Instead of taking the Sup point to point, the sum point to point is defined. So the process is then equivalent to the convolution of a Poisson train of deltas with a random pulse. The aim of this paper is to analyse textures through these two models, in order to infere their genetics through a given realisation of the process, i.e., to analyse the complete statistics of the germ functions and the density of the associated Poisson process in order to characterise a given texture. Experiments and results are provided which prove that the real textures can be understood as realisations of Boolean random functions (of linear and non-linear basis), and that it has been possible to infere the genetics of unidimensional Boolean random functions of linear basis with the algorithm proposed here. It has also been possible to do it with non-linear Boolean functions but only by imposing two restrictive conditions on the genetics of the realisation. (C) 1997 Elsevier Science B.V.
In this paper, a new coding method for multiview depth video is presented. Considering the smooth Structure and sharp edges of depth maps, a segmentation based approach is proposed. This allows further preserving the ...
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In this paper, a new coding method for multiview depth video is presented. Considering the smooth Structure and sharp edges of depth maps, a segmentation based approach is proposed. This allows further preserving the depth contours thus introducing fewer artifacts in the depth perception of the video. To reduce the cost associated with partition coding, an approximation of the depth partition is built using the decoded color view segmentation. This approximation is refined by sending some complementary information about the relevant differences between color and depth partitions. For coding the depth content of each region, a decomposition into orthogonal basis is used in this paper although similar decompositions may be also employed. Experimental results show that the proposed segmentation based depth coding method outperforms H.264/AVC and H.264/MVC by more than 2 dB at similar bitrates. (C) 2011 Elsevier Inc. All rights reserved.
MPEG-4, with its superior compression, interactivity and universal access, is the most promising future standard. MPEG-4 relies on a content-based representation so it can provide new functionalities such as content-b...
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ISBN:
(纸本)0819447145
MPEG-4, with its superior compression, interactivity and universal access, is the most promising future standard. MPEG-4 relies on a content-based representation so it can provide new functionalities such as content-based interactivity and scalability. Content-based coding, which encodes the objects within a picture, is one of the most important functionalities proposed by MPEG-4, and it has attracted considerable attention. Moreover, encoding the texture of an arbitrarily shaped object is an important part of object-based coding. Therefore, many researchers have being trying their best to solve this problem, and they proposed various methods to encode the texture of an arbitrarily shaped object. In this paper, we summarize several methods of arbitrarily shaped object coding including SA-DCT (Shape Adapted-DCT), EA-DCT (Expanded Arbitrary-Shaped DCT), Mean Replacement Padding and Low Pass Extrapolation Method (LPE). We also propose two new padding method of arbitrarily shaped object coding. Experimental results showed that the proposed methods have almost the same effect as LPE method, which MPEG-4 has adopted, so that it can improve the coding efficiency of DCT.
Files containing 3D objects, typically represented as 3D meshes with certain geometry and texture information, are very large. Therefore, not only do 3D objects take a lot of storage space, it is also extremely time-c...
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ISBN:
(纸本)0819437190
Files containing 3D objects, typically represented as 3D meshes with certain geometry and texture information, are very large. Therefore, not only do 3D objects take a lot of storage space, it is also extremely time-consuming to transmit them over the network for visualization. In addition, most 3D visualization applications need the entire 3D data file to render the 3D object even though the user may be interested in only a small part or a low-resolution version of the object. Progressive coding of 3D objects can resolve these problems. In this paper, we report our recent progress in progressive representation, transmission, and visualization of 3D objects. In our scheme, both geometry and the texture of the 3D object are progressively coded and transmitted. More perceptually important information is transmitted before the less important information, which allows the user to stop the transmission at any time and yet retain the best available perceptual quality of the object at that time. Furthermore, the visible portion of the object is transmitted first and the non-visible portion is transmitted later, or not transmitted at all, in order to save the overall bandwidth.
This paper proposes a new multi-layered image coding algorithm based on wavelet and matching pursuit transforms. The original image is divided into smooth and edge layer and texture layer, Different compression algori...
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ISBN:
(纸本)9781424420957
This paper proposes a new multi-layered image coding algorithm based on wavelet and matching pursuit transforms. The original image is divided into smooth and edge layer and texture layer, Different compression algorithms of coding are adopted to each different layer in order to achieve optimization for the entire image. Case studies have demonstrated that this coding method can capture texture and edge characteristics efficiently. Besides, the quality of reconstructed image is better than traditional single wavelet image coding algorithm at low bit rates.
this paper presents a HEVC based multi-view video codec. The frames of the multi-view videos are interleaved to generate a monoscopic video sequence. The interleaving is conducted in a way to increase the exploitation...
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ISBN:
(纸本)9781509054879
this paper presents a HEVC based multi-view video codec. The frames of the multi-view videos are interleaved to generate a monoscopic video sequence. The interleaving is conducted in a way to increase the exploitation of the temporal and inter-views correlations. The MV-HEVC standard codec is configured to work as a single layered codec, which functions as a monoscipic HEVC codec with AVC capabilities, and used to encode interleaved multi-view video frames. The performance of the codec is compared with the anchor standard MV-HEVC codec by coding the three standard multi-view video sequences: "Balloon", "Kendo" and "Newspaper1". Experimental results show the proposed codec out performs the anchor standard MV-HEVC codec in terms of bitrate and PSNR.
Palmprint recognition has attracted much attention in recent years. Many algorithms based texture coding achieve high accuracy. However they are still sensitive to local unsteady region introduced by variations of han...
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ISBN:
(纸本)9781457701214;9781457701221
Palmprint recognition has attracted much attention in recent years. Many algorithms based texture coding achieve high accuracy. However they are still sensitive to local unsteady region introduced by variations of hand pose and other conditions. In this paper we proposed a novel feature extraction algorithm, namely binary contrast context vector (BCCV), to represent multiple contrast distribution for a local region. Due to forming the local contrast value into a binary vector, contrast context could be used to match more effectively. Furthermore, by using BCCV we apply an adaptive threshold to mask the stable local region before matching. Our experiment results on public palmprint database shows that the proposed BCCV achieves lower equal error rate (EER) than other two state-of-the-art approaches.
textures can often be found in large areas of images and videos. They have different spectral and statistical properties as compared with normal (structural) components. Encoding them with ordinary video coders requir...
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ISBN:
(纸本)9781479946129
textures can often be found in large areas of images and videos. They have different spectral and statistical properties as compared with normal (structural) components. Encoding them with ordinary video coders requires higher bit rate and usually results are unsatisfying in perceived quality. Recently, different perceptual tools have been developed to estimate the perceived quality of textures taking into account models of human visual system. In this paper, we investigate and discuss the practical usability of one of these tools, namely STSIM, as a distortion function for selecting the intra-prediction mode and block partitioning of texture images in HEVC. We experiment few practical implementations to examine its performance compared with default metrics used by HEVC. Experimental results showed that the perceived quality of the decoded textures has been significantly improved specially for stochastic types of textures
3D-HEVC is the newest standard for compressing the Multi-View plus Depth (MVD) video. Inheriting from HEVC, 3D-HEVC presents a high encoding complexity by extra considering interview prediction. Under the encoding arc...
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ISBN:
(纸本)9781479983407
3D-HEVC is the newest standard for compressing the Multi-View plus Depth (MVD) video. Inheriting from HEVC, 3D-HEVC presents a high encoding complexity by extra considering interview prediction. Under the encoding architecture of 3D-HEVC, we develop fast algorithms for early decisions of CU splitting/non-splitting for both texture and depth frame coding. High correlation between the texture and depth domains is exploited such that when encoding one domain of information (texture or depth), the coding efficiency (RD characteristics or speedup) can be improved by adding suitably augmenting information from the other domain, thus achieving the so-called depth-assisted and texture-assisted coding. In texture coding part, optical flow features and depth edges are combined to form a feature vector for searching similar CUs in previously coded block buffers and inheriting the CU splitting decision accordingly. In depth coding part, optical flows and depth map features are used as inputs to a neural classifier for fast decision of CU splitting/non-splitting. Compared to the original 3D-HEVC implementation, our texture coding algorithm achieves a 46.6% of time saving at only 0.4% of bit rate increase and 0.04 dB of quality degradation. On the other side, our depth coding algorithm saves 35.8% of the encoding time at 2.65% of bit rate reduction and 0.16 dB of PSNR degradation. In comparison to prior works [4][5][10], our algorithm achieves more time saving at comparable bit rate increase and PSNR degradation.
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